There is known a vehicular lamp including a low beam optical system including a low beam lens and a low beam light source, and a high beam optical system including a high beam lens and a high beam light source (see, for example, Patent Document 1 (FIG. 1, etc.)).
In Patent Document 1, a low beam light distribution pattern can be formed by turning off the high beam light source and turning on the low beam light source. In addition, a high beam light distribution pattern can be formed by simultaneously turning on the high beam light source and the low beam light source.